Cellulose ether solvent and composition



Patented Sept. 12, 1922.

STEWART J. CARROLL, OF ROCHESTER, NEW YORK, ASSIGNOR TO EASTMAN KODAKCOMPANY, OF ROCHESTER,

NEW YORK, A CORPORATION OF NEW YORK.

CELLULOSE ETHER SOLVENT AND COMPOSITION.

No Drawing.

To all whom it may concern:

Be it known that I, STEWART J. CARROLL,

'a citizen of the United States'ot America, residing at Rochester,

Cellulose Ether Solvents'and -Compositions (Case E), of which thefollowing is a full,

- clear, and exact specification.

This invention relates to solvents for making strong solutions ofcellulose ether and also relates to the cellulose ether compositionsproduced by the aid of such solvents. One object of my invention-is toprovide a solvent which will dissolve such large proportions ofcellulose ethers that thiclr or viscous flowable solutions may beobta1ned for use in plastic and film mal nng arts. Another object of myinvention is to provide a cellulose ether solution which may bemanufactured into strong, flexible, transparent film on the machines andby the methods now in use.

In U. S. Patent No. 1,188,37 6, Lilienfeld, June 20, 1916, there aredisclosed a series of alkyl ethers of cellulose. Certain of these arepractically insoluble in water, and my invention relates but is notlimited to the ethers having that property. While such ethers form thinsolutions in the lower monohydroxy aliphatic alcohols or in ethylenechloride, it has been gle solvents by themselves will not dissolve asufficient proportion of the ethers to make 10 to 60 parts of methylalcohol, orI. may

a desirably thick flowable composition or dope, such as may be used inthe manufacture of photographic film base by the customary methods, andin the other plastic arts.

strong and useful solvent may be prepared by mixing ethylene chloridewith one or more of the lower monohydroxy aliphatic alcohols.

While the proportions in which the ingredients may be mixed can bevaried considerably, the following. examples illustrate useful ranges. Imay, for example, mix 90 to 40 parts by weight of ethylene chloride withuse 10 to parts of ethyl alcohol in place of the methyl alcohol. hilethe amounts of ethers which may be dissolved in my compound solvents canvary Widely, it is noted,

'tive freedom rom color.

found that the sinby way of illustration, that a useful viscous flowablesolution can be obtained by dissolv- Application filed April 5, 1921.seriarnaaaamo.

mg one part of water-insoluble ethyl cellulose III 5 parts of one of theabove mentioned compound solvents. Other substances whichimpartadditional suppleness, or incombustib1l1ty or other qualities tothe film may then be added to the dope, such, for instance, astrt'iphenyl or tricresyl phosphate, camphor, e c.

The ingredients are of the ordinary commercial type and sufficientlypurified for the process of film manufacture, so as to give a dopey1eld1n films having the proper rela- The viscous-flowable dope abovedescribed can be used in connection with the usual film-formingapparatus without the necessity of expensive .cellulose, comprising from90- to 40' parts by weight of ethylene chloride and 10 to '60- parts ofa lower monohydroxy aliphatic alcohol. I

3. A compound solvent for alkyl ethers of cellulose, comprising amixture of ethylene chloride and methyl alcohol.

' 4. A viscous flowable film-forming composition, comprising an ether ofcellulose dissolved in a mixture of ethylene chloride .and a lowermonohydroxy aliphatic alcohol.

5. viscous flowable film-forming composition, comprising an alkyl etherof cellulose dissolvedin'a compound] solvent containlng from to 40 partsby weight of ethylene chloride and 10 to 60 parts by weight of a lowermonohydroxy aliphatic alcohol.

"6. composition of matter, comprising 1 part of water-insoluble ethylcellulose .dissolved in approximately 5 parts by weight of a compoundsolvent containing ethylene chloride and methyl alcohol.

Signed at Rochester, New York, this 26th day of March, 1921.

srnw J. CARROLL.

